Sheriff Joe Arpaio is teaming up with an action star to tackle school violence.

Steven Seagal, 60, star of "Above the Law" and "Under Siege," will lead members of the Arizona sheriff's volunteer posse through a simulated school shooting today.

The volunteer posse, which is nearly 3,500-strong, has been used to patrol shopping malls during the holiday season and scope out undocumented immigrants, and now Arpaio plans to have them patrol areas surrounding schools in Arizona's most populous county, Maricopa, which includes Phoenix.

"Volunteers will learn operating procedures on how to handle one, two and three shooter scenarios as well as room entry tactics and hand to hand combat," the Maricopa County Sheriff's Office said in a news release.

Two dozen high school students have volunteered to participate in the simulation, and SWAT deputies will pose as the shooters, the release said.

Seagal occasionally worked as a deputy for the Jefferson Parish sheriff in Louisiana and had a reality show "Steven Seagal: Lawman."

Arpaio, the self-styled "America's Toughest Sheriff," began sending armed posse members to patrol schools in January, following the Newtown, Conn., elementary school massacre and a more local threat that resulted in the Dec. 20 arrest of a 16-year-old student at Red Mountain High School in Mesa, Ariz., for a plot to bomb the school and shoot the students and faculty.

Arpaio told ABCNews.com in January that volunteers will receive 100 hours of training and drive marked vehicles. In some cases, he said, they will be armed with automatic weapons.

"I believe we should put police officers in school, in uniform, armed," the sheriff said. "But so far all the politicians do is talk, talk, talk, and so we're out there doing something."